Vagus Control of Pancreatic Function Experimental Insulin Resistance

The first contribution to the knowledge of the nervous control of glycemia was made by Claude Bernard who showed that hyperglycemia follows piq#{252}re of the floor of the fourth ventricle. It is not improbable that in such a procedure the vagus nerve would be affected due to close proximity of its nucleus to the site of injury. PflUger (22) found that destruction of the nerves leading to the pancreas produces the same effect as complete pancreatectomy. This author also gave numerous examples of hyperglycemia caused by curare, atropin and other substances affecting the nervous system. Kuntz (17) quotes De Corral and states that in 1918 it was finally proved that a marked hypoglycemic effect is produced in dogs after stimulation of the vagus below the diaphragm, the nerves supplying the liver having been destroyed surgically. While after denervation of the liver alone hyperglycemia results. The vagus control of pancreatic function in carbohydrate utilization has been reported since by numerous investigators (5). The interdependence between the secretory work of the pancreas and the pancreatic control of carbohydrate metabolism described by one of us (6, 7), has been confirmed by several investigators. Many years ago it was established, mostly by works of Heidenhain and Pavlov (21), that the vagus is the chief regulator of the external secretion of the pancreas. During the last few years several cases of insulin resistance have been recorded in clinical literature. Those observed by